This invention relates to a curb forming apparatus, and more particularly to an attachment to the slip form of a curb forming apparatus to produce low curb profiles.
Self-propelled curb forming machines are well known, and have been in use for several years. These machines typically form continuous curbs along newly constructed roads and the like by causing concrete in a plastic or flowable state to be molded by a slip form mounted on the machine as it is propelled along the road. The plastic concrete has sufficient strength to retain the contour given to it by the slip form. An example of such a curb forming machine is the Commander III manufactured by Gomaco Inc.
A slip form typically has the profile of the desired profile of the finished curb or finished curb and gutter. It is a common requirement of curb construction to accommodate ramps and driveways, particularly in residential areas. To this extent, several methods have been developed to form the low profile curb required by, for example, a driveway. The prior art discloses methods wherein a cut off plate is selectively placed in the slip form in order to adjust the height of the finished curb. An example of one such device is disclosed in U.S. Pat. No. 3,797,958 issued to Lofaro (the Lofaro patent). A second example is Canadian Patent 2,043,773 issued to Cerquozzi et al. (the Cerquozzi patent).
In the Lofaro patent, the cut off plate is pivotally connected to the rear end of the slip form so that it is lowered into place when a low profile curb is to be formed. The excess concrete that is separated by the cut off plate is discarded or reclaimed for reuse.
The Cerquozzi et al. patent uses a plate within the slip form, which is mechanically or hydraulically lowered into the slip form in order to reduce the height of the curb portion.
In both of these methods, the finished curb does not have a smooth finish and considerable manual effort is required in order to produce a smooth curb surface.
U.S. Pat. No. 5,662,431 issued to Colvard, provides a system wherein the slip form for a full curb is removed and a replacement slip form having a new low curb profile is installed. This replacement operation requires that the curb forming operation stop during the replacement, and the resulting transition between the different profiles in the curb results in poor finish, again requiring considerable manual activity to provide an acceptable finish.
Handwork with conventional systems requires that a skilled workman lay supporting lumber on both sides of the curb to support the curb during tooling. Next, a finisher floats and tools the transition from a high curb profile to a low curb profile and the entire dropped section. The concrete is then manually smoothed and finished. With a typical driveway requiring up to one half hour for manual finish, this is extremely time consuming and adds considerably to the total cost of the operation.
Therefore, there is needed a means to allow the formation of various curb profiles, eliminating the need for excess hand work.
The present invention alleviates the aforementioned limitations by providing an attachment, known herein as a moveable tailpiece, for a curb forming machine, which is selectively rotatable into place on the back of the slip form. Preferably, this is effected via a hydraulic cylinder operating on a sprocket combination. The tailpiece is shaped to the profile required by the low curb section, and because it is held firmly in place, provides a smooth finish to the concrete such that very little to no manual finishing is required.
Thus, according to one aspect, the invention provides a moveable tailpiece for a curb forming machine for producing low curb profiles. The curb forming machine comprises a slip form. The tailpiece is shaped for rotation within the slip form between a parked position wherein the tailpiece is not in contact with the curb to be formed and an engaged position wherein the tailpiece is in contact with the curb to be formed.
According to another aspect, the invention provides a method of producing a curb having a changeable profile. The method comprises the steps of positioning a moveable tailpiece of a curbmachine to an engaged position, wherein the tailpiece is in contact with the curb, the tailpiece having a profile corresponding with the modified profile of the drop curb to be produced, and propelling the curbmachine forward over the area where the curb is to be produced.
There is a significant advantage in using a moveable tailpiece attachment in a curb forming machine. The tailpiece provides considerable savings in time and resources in the production of lowered curbs for driveway access and handicap ramps and sidewalks, The moveable tailpiece also eliminates the need for floating and tooling dropped sections of curb. Since hand finishing is now only required at the transition between profiles, the moveable tailpiece results in considerable saving of labor.
Other aspects and advantages of embodiments of the invention will be readily apparent to those ordinarily skilled in the art upon a review of the following description.